Process of making wood-alcohol.



treat crude pyroligneous acid by a'simple,

1 UNITED STATES PATENT OFFICE. f

HARRY O. CHUTE OF CLEVELAND, OHIO.

PROCESS OF MAKING WOOD-ALCOHOL.

Specification of Letters Patent.

Application filed March 31, 1906' Serial ND- 309,115-

' steps, all as more fully hereinafter set forth,

matters of novelt being particularly pointed out in the appended claims.

In the art the term wood-alcohol is used to denote methyl alcohol containing more or less acetone and other low-boiling constituents of pyroligneous liquor or acid.

Pyroligneous liquor or acid is the aqueous portion of the condensed products from the vapors arising from the destructive distillatlon of wood, separated as far as possible by settling from the tar and-other insoluble impurities, and it consists, essentially, of a Watery solution of acetic and other acids, meth '1 alcohol, acetone, and certain other su stances of minor importance. In addition, it is lnyariably contaminated by oily bodies held in'solution and suspension by the influence of the acetic acid, &c. Other impurities consist of aldehydes and higher ketones, which are unstable and are sensitive to alkali polymerizing and resinifying in presence of excess of base. 7

It 1s the object of the present invention to ready, and cheap method for the recovery of the several values thereof, doing this b an organized succession'or steps, each resu tin 1n the formation of a valuable product, an the several steps of the method as a whole co operating to deliver purified wood-alcohol in commercial form.

A number of methods are now in use for recovering wood-alcohol from this pyroligneous llquor'. One much used in chemical Works employin retorts preliminarily distils the whole bulk of volatile liquid to get rid of nonvolatile impurities comprising tar, &c. This distillate is barely neutralized with llme to form acetate and the alcohol distilled from the neutral liquid so formed. It is nec- 'essary to guard against excess of alkali,

which here polymerizing andresinifying the unstable impurities would render the acetate no doubt, retained bythe acid li nately the oil bodies, which are foul-smelling, distil'wit the acid and dissolve in it on Patented J'iii a, 1906.

account of its great bulk and on redistillation accompany the alcohol on account of their high va or tension, rendering 1t milky on addition 0 water.

In another method much used in kiln charcoal lants an attempt is made in the first d1st1l ation to efiect a rou h separation of al- -cohol and acid, and for this purpose it is cusmore than tomary to distil off somewhat one-half to obtain the alcohol. This distillate contains considerable acid and is quite dilute, not usually containin more than three per cent. of alcohol. e residue in the st1ll is substantially free of alcohol.-

This weakness of the distillate is due to the large volume distilled over. Besides the aci and the three per cent. of alcohol it contains the objectionable impurities referred to. In a distillate of this nature and strength they are apparently held in solution or susension, or both. The next operation flper: ormed is to neutralize and fractionate o the alcohol previous to evaporating the neutralized liquor for acetate. Here, again, the oily im urities are reinforced on neutralization an pass forward to contaminate the-alcohol, and the other unstable bodies are not polymerized or condensed, owing to lack of excess of alkali. 4 v

The same is true of a third process used for making brown ac etatec. e., acetate ,containing tar.in which thepyroli neous distl ed to acid is directly neutralized and obtain the alcohol. I have, however, discovered that in an'acid distillate containing between ten and twenty-five per cent. of alcohol these oily impurities are substantially insoluble and settle out readily. Some are, uor in the still in making such a concentrate In my new process I therefore directly --fractionate the pyroligneous acid in' any suitable still arranged to deliver concentrated distillates, such as an ordinary continuouscolumn still, carryingon the distillation so as to obtain a distillate between the strengths mentioned-viz., ten to twenty-five per cent.

of alcohol. This distillate I allow to stand' and settle for some time. Of the codistilled impurities going over with the wood-spint distillate.

-ioo

many are insoluble in spirit of this strength and separate 1n.oily droplets, coalescing on standing as a heavy underlying oily layer. These oils have great'solvent properties and are useful for dissolving many organic compounds which are not acted upon b j ordinary or anic solvents. Because their strong 0 or they are also useful for denaturgrain-alcohol. Other impurities, however, are soluble and remain in and contaminate the supernatent' layer of spirit. These latter impurities I find are quite sensitive to the action of alkali, being probably largely 1c ketonoid or ,aldehydic in their nature and with alkali polymerizing or resinifying with formation oftarry insoluble bodies. Therefore, after decanting the alcoliol from the se aratedoily bodies I add an excess ofan I 5 a ali, as lime. Reaction soon sets in, as is shown by the development of yellow color, the familiar color known and carefully avoided inworking with pyroligneous acid as an evidence of overliming. It is here, however, advantageous and'not detrimental. As

the reaction progresses alkali-resinous matters separate and form a precipitate. Theseresinous bodies formed by the action of the alkali on the aldehydic and ketonic impurities form a mass of novel and useful characfrom crude pyroligneous ac d which conslsts teristics, it being substantially a dye resin, being susceptible of use as a dyestufi, as it stains organic matters bright yellow when roperly applied, and also ofuse as a resin. eing formed from a liquid from which the oily and tarry impurities have been removed w by previous treatments, it is substantially pure. I do not claim this material herein specifically, but reserve the right to file. -a

separate application therefor. The spirit decanted from this precipitate willbe found 7 much improved in quality, having been freed from these two classes of impurities, and I am therefore enabled to directly rectify in 49 any rectifying continuous column producin by this one redistillation alcohol of standar eighty-two per cent. strength, but of such purity that it is miscible with water in all proportions and cannot be refractionated into portions milking with Water.

It is obvious that the described-process makes practical a ready, cheap, a d simple reparation of a high-grade alcohol directly om crude pyroligneous acid.

To recapitulate, myprocessin its preferred embodiment consists in 'fractionatin pyrol gneous acid in the acid state to o tain a concentrated distillate of such alcoholic strength that oily impurities become insolu- 5 5 ble preferably between ten and twenty-five per cent, settling out the separated oily im-' purities, drawing off the clear liquid from the setthngs, polymerizing and resinifying alkali sensitive impurities w1th alkali in excess, and refractionating to obtain a erfectly-miscible strong alcohol.

What I claim is a V 1. The process of preparing wood-alcohol from crude p oligneous acid which consists indistlllmg om said acid a concentrated excess of alkali.

allowing said distillate to stand to permit separation of impurities, decanting off the clear liquid and adding thereto an excess of alkali.

3. The process of preparing wood-alcohol from crude pyroligneous acid whichconsists in distillin from said acid a concentrated distillate 0 between ten and twenty-five percent. alcoholic content and of acid nature, allowing said distillate to stand to permit separation of impurities,- decanting off the clear liquid, adding theretoan excess of alkali and decanting away from the resinous deposit formed. t

4. The process of'preparing wood-alcohol go in distillin om said acid a concentrated distillate 0 between ten and twenty-five per cent. alcoholic content and of acid nature allowing said distillate'to stand to permit se9a 9 5 ration of impurities, decanting oil the clear liquid, adding thereto an excess of alkali, de-

-canting and refractionating the decanted liquid to produce strong alcohol.

5'. The process of preparing wood-alcohol from crude p 'oligneous acid which consists in distillin fi om said acid a concentrated distillate 0 between ten and twenty-five per cent. alcoholic content and-of acid nature, allowing said distillate to stand to permit separation of impurities, decanting off the clear liquid,- adding thereto an excess of alkali, de-

canting and refr'actionating the decantin liquid to produce perfectly-miscible alcoho of above. eighty per cent.

= I 11o 6. The process of preparing wood-alcohol from crude pyroligneous acid which consists in distilling from said acid an acid product of an alcoholic strength wherein oily impurities are insoluble, allowing the same to stand 11 5 to permit se aration of such impurities, and decanting o the clear liquid.

7. .The process 0f preparing wood-alcohol from crude yroligneous acid which consists in distilling om said acid an acid product of 51 20 an alcohohc strength wherein oily impurities are insoluble, allowing the same to stand to permit separation of such impurities, decanting off the clear liquid and a ding thereto an 8. The process of preparing wood-alcohol from crude pyroligneous acid which consists in distilling from said acid an acid product of an alcoholic strength wherein oily impurities are insoluble, allowing the same to stand to I30 permit separation of such impurities, decantmg ofi the clear liquid, adding an excess of alkali and decanting away from the resinous deposit formed.

9. The process of preparing miscible woodin allali, decanting away from they resinous deposit formed, and refractionating the de- 'canted liquid to form a strong alcohol of above eighty per cent. and perfectly miscible alcohol from crude p oligneous acid which consists indistilling 'om said acid an acid product of an alcoholic strength wherein oily mpurities are insoluble, allowing the same to stand to permit se aration of such impurities, decanting ofi t e clear liquid, adding an excess of alkali, decanting away from the resinous deposit formed, and refractionating the decanted liquid to produce strong miscible alcohol.

10. The process or preparing wood-alcohol from crude pyroligneous acid which consists in distilling from. such acid an acid product of an alcohohc strength wherein oily impurities are insoluble, allowing the same to stand to permit separation of such impurities, decantofi theclear liquid, adding an excess of with water.

In testimony whereof I affix my signature in the presence of two witnesses.

HARRY o. CHUTE. Witnesses BLANCHE 'L. CHADwELL, K. P. MCELROY. 

